Quaternary compound of benzethonium chloride and saccharin



QUATERNARY COMPOUND OE BENZETHONIUM CHLORIDE ANDSACCHARIN August I. Pacini, Tarrytown, LesterE. Amster, New York,

and Richard A. Duif, Levittown, N. Y.

No Drawing. Application January 31, 195

' Serial No; 562,609 a 1 Claim. (Cl. 260-501 through regular commercial channels under a variety of" trade names. It can be "readily appreciated that a wide variety of cationic germicides will eventuallybe made 7 available as the possibility of variation in chemical structure with the quaternary ammonium central characteristic offers a widescope of compounds.

Patented Mar. 25, 1958 Because of the lowered surface tension of benzethonium chloride solutions, they are enabled better to penetrate inaccessible folds, crypts, follicles and other bacterial hideaways present everywhere in the mucous surfaces of the fauces. Such easier access to nests of bacteria that may .ordinarily escape viscous and non-surfactant solutions respond to the bacteriostatic and/or bactericidal properties of surfactant quaternary, thereby yielding improvedhygienic advantages'ot-many sorts including the control and even the prevent-ion of local and/ or systemic infections commonly known to develop at andfrom this portal of entry; Such organisms embedded in the mucous membranes of the fauces can escape attack by aqueous. and even alcoholic mouthwashesidespite their content of ordinary antiseptic ingredients when these are unable to reach other than the most superficially disposed germs. This istrue also of quaternary compounds and other antiseptic substances that are made into sugared confections since. the ratio of sugar to antiseptic material is such thatin the dissolution of the lozenge, .tro'che,

In accordance'withthe present invention, we have found, contrary to; the teaching of prior art,that nonbitter and highly effective bacteriostatic and bactericidal compounds may be prepared as a reaction product, or mixture of quaternary ammonium compounds with saccharin. t r

Thus itis seen that quaternary ammonium compounds are characterized by theirability to exert powerful bacteriostatic and/ or bactericidal effectiveness in dilutions that are completely non-toxictothe human organism, by an ability toreduce surface tension thereby exerting more than ordinary surfactant penetration, and'by thejfurther property of exercising pronounced deodorant capacity. Such quaternaries, however, are intensely bitter to the taste causing them to be rejected for local and/or systemic effectiveness where indications exist for the use of their other properties. Typically illustrative of a useful quaternary for this purpose is benzethonium chloride U. S. P. XV, 'represented'by the following chemical configuration:

l on: on.

OHri-GHr+-O ontorno cream-ripen.-

Ha CH CH3 Benzethonium chloride solution is recognized in U. S. P. XV as a local anti-bacterial suitable for topical application as a 1: 1000 solution to'the skin, or a 1:5000 solution to the eye or nose. It is clear, colorless, odorless but intensely bitter. Sprayed into the throat in concentrations of 1:l00,000, aqueous solutions 'of benzethonium chloride U. S. P,. exercise valuabletherapeutic aid, particularly with respect 'to the control of inflammations that represent beginning surface infections. Benzethonium chloride is also known asPhcmerol Chloride, Phemeride, and Hyamine, andis described in the Merck Index, 6th edition, page 735. .Preparationof this compound is described "in U. S..-Patents No. 2,115,250, 2,170,111, and

pastille, cough drop" orbther, a thick viscous syrup is at first formed serving as a barrier by osmotic hindrance to the easy accessibility of the antiseptic to the depths required for effective reactivity. Such candies are useful as demulcents, but can be shown to exert only the barest and practically always a nil bactericidal value as contrasted with the same ratio of quaternary in an aqueous solution or in a sugar-free tablet or equivalent.

Many quaternaries, benzethonium chloride included, show a wide range of incompatibility. For example, on page 25, of Surface-Active Quaternary Ammonium Germicidesfiby Carl A. Lawrence, Academic Press Inc., New York, 1950, among other substances incompatible with alkayldimethylbenzylammonium chloride, mention is made of saccharin. Such incompatibility is surmised when in the mixture of an aqueous quaternary solution produced for pharmaceutical compounding with other ingredients, a physical change appears in which a precipitate results. It is important to realize also that occasional physicaladmixtures maybe made without the separation of a precipitate, but attended, nevertheless, with loss and even extinction of all bactericidal and/or bacteriostatic capacity. e

When benzethonium chloride U. S. P. is mixed in molar equivalents withsodium saccharin U. S. P. in solution, and the mixture boiled, the following changes in physical appearance are observed: An oily liquid showing a specific gravity of approximately 1.14 separates as a layer of the oily layer is're gulated entirely by the solute con centration of the aqueous layer so that when this is great (above 1.14) the oily layer floats, and when it is small (below 1.14) the oily layer sinks.

Separation of the layers and subsequent evaporationto dryness of the aqueous phase (non-oily layer) yields a crystalline solid with characteristics that distinguish it from either sodium saccharin or benzethonium chloride.

This solid is bacteriostatic and/ or bactericidal. It depresses surface tension such thatan 0;l'%'- solution of the solid gives approximately 36 dynes'per'square centimeter. It is not bitter, but somewhat sweet like the saccharin from which it is derived without, however, developing a bitter after-taste such as many individuals frequently experience in the case of saccharin. It has a melting point in excess of either sodium saccharin (226 C. to 230 C.) or benzethonium chloride (between 160 C. and 165 C.), and somewhere between 280 C. to 285 C. On chemical analysis, it yields very close to the following composition:

. Percent Carbon 62.0 Oxygen 12.2 Nitrogen 4.3 Hydrogen 7.3 Sulfur 4.9 Chlorine 5.4 Sodium 3.5

From this compound, it is possible to separate sodium chloride. The composition suggests that some measure of interaction has resulted between benzethonium chloride and sodium saccharin yielding, in essence, benzethonium saccharin and sodium chloride. Such a reaction would be represented by the equation previously indicated.

Whether or not this precise chemical interaction takes place is still a matter of intensive investigation, the result of which is inconsequential with respect to the more important finding that the mixture or compound so produced exhibits the following properties:

(1) It is bacteriostatic and/or bactericidal to an extent within the range that will be indicated subsequently.

(2) It lowers the surface tension of water so that 0.1% solution in water gives a value of 36 dynes per square centimeter.

(3) It retains some of the deodorant properties of the original benzethonium chloride from which it is derived.

(4) It retains the sweetness, but not the after-bitterness, of the sodium saccharin from which it is derived.

(5) It is completely devoid of the intense bitter taste of the original benzethonium chloride when used in equivalent concentrations based on equivalent bactericidal effect.

(6) The substance is soluble in water and it is not precipitated therefrom by many of the substances that precipitate benzethonium chloride.

It is obvious that the compound and/ or mixture retains the desirable therapeutic virtues of the benzethonium chloride from which it is derived and eliminates the bitterness that has precluded the use of benzethonium chloride in forms where it can exert its greatest therapeutic effectiveness.

The production of this compound and/or mixture, is illustrated in the following exemplary procedure:

Example 1.150 grams of benzethonium chloride are dissolved in 400 to 600 cubic centimeters of water. 375 grams of saccharin sodium are dissolved in 400 to 600 cubic centimeters of water. These are not in the proportion of the molecular Weight of each ingredient, the molecular weight of benzethonium chloride being 466.11 and that of sodium saccharin being 241.21. Both solutions are mixed and brought to a boil, the boiling maintained for one hour. In the course of boiling, a turbidity develops due to the dispersion of a water insoluble oily layer. After boiling, and on standing, the yellowish oily layer separates out at the bottom of the mixture. This layer seemingly retains some water and may measure from 8 to 10 ounces in volume. Overlaying the oily layer is a clear supernatant fluid. The clear fluid is removed from the oily layer, filtered and evaporated to dryness over a water bath. A recovery of from 250 to 290 grams of a white crystalline solid is obtained, the weight depending in part on the completeness with which the water layer is separated from the oily layer, and in part on the thoroughness with which the water bath drying is effected. I

The solid compound has a melting point above 280 C., is soluble in water, alcohol and acetone, is slightly sweet with no residue of bitterness and is bactericidal and/or bacteriostatic. For instance, a 1225,000 concentration in Water shows a phenol coefiicient of approximately 1:1,500,000. An 0.1% solution of the solid shows a surface tension of 56 dynes per square centimeter. Administered in doses of 10 milligrams daily to a human subject over a period of four months, no evidence whatever of acute and/ or toxic distress is observed. In lower animals, the LD-50 is greater than that usually stated for benzethonium chloride, being of the order of 750 instead of 500 for mice, and 900 instead of 765 for rats. An aqueous solution of the solid in water shows a pH of approximately 7.2 as distinguished from a pH of 7.0 for a similar solution of equivalent concentration of benzethonium chloride. The approximate analysis is about as follows:

Percent Carbon 62.0 Oxygen 12.2 Nitrogen 4.3 Hydrogen 7.3 Sulfur 4.9 Chlorine 5.4 Sodium 3.5

Since sodium chloride is present in the recovered material, and the percent of sodium and chlorine found are in stoichiometric proportion, such as appear in sodium chloride, and because the remaining composition answers to a stoichiometric combination of benzethonium and benzodulfimide, it is hypothecated that the product in question can be benzethonium benzosulfimide. If this hypothecation is correct, the resultant would represent, in part, the chemical reaction given previously.

Whether the hypothesis is true or false is not immedi ately consequential to the finding that the compound desired is achieved in the mannerdescribed and presents the properties outlined above, a surfactant, water soluble, odorless, slightly sweet and completely nonbitter, deodorant possessing approximately the same order of bacteriostatic and/or bactericidal effect as that of the original benzethonium chloride and greater than that of the sodium saccharin from which it was derived.

It is not necessary that the proportions indicated in Example 1 be followed meticulously in order to obtain the product. The same effect is obtained if other proportions are employed, the difference being in the yield and in the degree of sweetness presumably owing to more or less presence of unaltered sodium saccharin. For example:

Example 2.-A gram molecular equivalent of benzethonium chloride, approximately 466 grams, and a gram molecular equivalent of sodium saccharin, approximately 241 grams, are dissolved in about three liters of water. The solution is boiled for one hour. Approximately 530 cubic centimeters of oil separates out and some 330 grams of utilizable compound are derived by evaporating the water phase.

Example 3.- grams of benezthonium chloride are dissolved in 400 to 600 cubic centimeters of water. 375 grams of saccharin are suspended in 400 to 600 cubic centimeters of water. The solution andsuspension are mixed and heated to boiling. After about an hour of boiling, a semi-solid residue will separate leaving a highly acid supernatant layer. The pH of this layer is about 1.5. Sufficient sodium hydroxide is now added completely to neutralize the solution and boiling resumed. The crystalline portion of the solids dissolves and a clear yellowish oily layer separates. From 250 to 300 grams of debittered quaternary active solid is recovered from the filtered and evaporated water layer. The formation of acid in this synthesis illustrates the ionic split of the i of the group are as follows:

benzethonium and saccharin, the cationic hydrogen of -Emulsept: N (higher acylesters of colamino formylthe saccharin combining with the anionic chlorine of the methyl) pyridinium chloride 1 benzethonium to form hydrochloric acid, just as in Example l, the cationic Sodium of the sodium .saccharin II II combines with the anionic chlorine of the benzethonium [CH(CH2)"TC O (CH1)TTNTO OHTr\ 1 chloride to produce sodium chloride.

Quaternary ammoniums which'are suitable for the practice of ourinvention and which are representative lsothan Q: Laurylisoquinolinium bromide CHs(CH2)n-N 10 Compound C. T. A. B., Cetavlon: Cetyltrimethylammonium bromide In testing compounds of our invention following (3113 7 cultures may be used as test organisms: (l) Escherichia cn mmm-qm-on coli, a heat resistant strain from the National Institutes E of Health; (2) Aerobacter aerogenes from the American Type Culture Collection; (3) Aerobacter aerogenes, a Product QB: Stearyltrlmethylammon um bromide capsulated (slimy) strain found in paper mills; (4)

0H: v crococcus aureous, isolated from drainage in wounds; (5) CHa(CH2 1, 1lI CH3 Br Stretococcus crentoris, from cheese starter organisms; H a (6) Bacillus subtllzs, from American Type Culture Collection; (7) M-23, mesophilic flat sour strain isolated onyxldel Oleyldimethlethlammomum bl'omlde from beets, by the laboratory of the National Canners" CH3 Association; (8) No. 1518,sfacultative thermophilic flat CH CH OH CH B sour strain isolated from peas by the laboratories of the 3 m rr National Canners Associatioh; (9) No. 1503, obligate thermophilic flat sour strain isolated from corn, by the Iothan Lauryldlmethylchlorethoxylammomum c laboratories of the National Canners Association. ride The non-spore-bearing cultures are grown in 9 cc. of 0113 broth (tryp'tone 5 g., glucose 1 g., bacto-beef extract 3 g., l 4 distilled water 1 liter). Only 24 hour subcultures of 24 [CHrwHnu N (CH2)0 (C]E[m -C1101 hour cultures are used in germicide tests, and at least H3 three successive transfers (at least 24 hour intervals) Nopoc QCL: Lauryldimethylbenzylammonium chloride are made prior to each test.

l- Tllie sporsJ-forming types anteidgrownloii5 slanlgs (mediurr): simi ar to a ove containing a itiona g. acto agar CH3(CH2)H-N GH C1 in 6 oz. fiat bottles. The slants are inoculated b wash- I a Y 0113 ing the surface with a 24-hour culture and incubated for Hyamine 1622, Polymine D, Phemerol: Diisobutylpheone week. The bottles containing the cultures are then noxyethoxyethyldimethylbenzylammonium chloride 40 e at 5 Until used To P p a culture the 0H: CH3 133 [CHa-(E-CHs--Q-OCHzCHzOCH2CH2-N-CHzc1-H2o 5H3 CH3 7 I 41H: Hyamine 10X: Diisobutylcresoxyethoxyethyldimethylgermicidal tests, 120 cc. of a tryptone, glucose-beef exbenzylammonium chloride tract broth are added to the slant and the bottle shaken B. T. C., Roccal, Zephiran: Alkyl (C H to C H dito suspend all growth. Nine cubic centimeter amounts methyl 3,4-dichlorobenzylammonium chlorides of the suspended culture are transferred to sterile tubes and boiled for six minutes and quickly chilled.

The cultures of both spore-forming and non-spore- O,.Hz,.+1N0H, 01' forming organisms are suspended in 9 cc. amounts of E broth for the germicide test. By plate counts and cornparable nephelometer observations the broth suspensions Tetrosan: Alkyl (C8H17 to 01 1 137) dimethyl 3,4-dichloroare standardized to approximately 500,000,000 Organisms benzylammonium chlorides per cc.

1 The routine test procedure includes the use of 1 cc. CH3 0 of germicide solution of 10 times the desired final con- I centration added to the culture suspension and shaken. C1 7 6 This method of adding a smaller amount of germicide to a larger amount of culture is preferred to the phenol coefficient method of the Food and Drug Administration Isothan Q4: Laurylpyridinium bmmlde in which a smaller amount of culture is added to a larger volume of germicide. It should be noted that [CHs(C 2)11- JB this procedure constitutes a more severe test of the germicidal ability than the corollary of adding small amounts ceepryn. cetylpyridinium chloride of cultures to large amounts of germicide as followed in the phenol coeflicient procedure. Results by this method a appeared to show fewer discrepancies (skips) and are F more capable of reproduction than results obtained by ing the water soluble reaction product of benzyldimethtetramethylbutyl-phenoxy)eth0xy] ethy1}-amrnonium chloride and saccharin.

References Cited in the file of this patent v UNITED STATES PATENTS 2,725,326 Shibe et a1 Nov. 29, 1955 

